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Meeting at St. John's tomorrow

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Stephen Guerin

Meeting at St. John's tomorrow

As a reminder, we'll meet back at St. John's tomorrow, Jan 4.

-S

____________________________________________________________________
Stephen.Guerin at Redfish.com
www.Redfish.com
624 Agua Fria Street, Santa Fe, NM 87501
mobile: (505)577-5828
office: Santa Fe, NM (505)995-0206 / London, UK +44 (0) 20 7993 4769

Hugh Trenchard

observations of complex phenomena while in Mexico

I am a lurker on this listserv and find many of the discussions here
interesting and valuable. Recently I was in Mexico and noticed a couple of
interesting complex phenomena I thought I would share with this group.

The first relates to frigatebird formations and ties in with observations of
these birds I made last year. Last year, when in Mazatlan, I noticed that
frigatebirds often hover and glide for several minutes at a time without
flapping and that they tend to glide in disorderd configurations until they
spontaneously undergo a phase change (it seems to me) when they align in vee
formations - still gliding nonetheless. These are fantastic sights to see,
since the birds seem to hang in the air in these vee formations without
passing across the sky at the relatively high speeds of geese, for example.

This year, in Cancun, I noticed frigatebirds gliding in disordered
configurations and, waiting patiently for the phase change, I was
disappointed when these changes did not occur. I wondered if I was
imagining the alignments I saw last year in Mazatlan, but fairly certain I
wasn't, I speculate why the phase changes did not occur among the birds I
saw in Cancun. Firstly it's possible the frigatebird colonies on the
Caribbean side of Mexico simply don't undergo these formations, being a
slightly different sub-species or what have you. Perhaps, but I hypothesize
that the wind speeds are the primary factor in determining whether formation
phase changes occur.

In Mazatlan last year in late Sept/early October, the wind speeds were low,
I recall. In Cancun, wind speeds were significantly higher. I suggest that
gliding in vee formations can only occur between a certain range of wind
speed - if wind speed is too low, the birds cannot glide at all; if too
high, they can glide, but they cannot align in vee formations. The critical
range allows frigate birds to draft when gliding behind another while
maintaining position, but above the range the drafting effect is too high
and the birds get "sucked" through - or tend to fall, it looked to me - the
low pressure areas and cannot hold their positions.

Drafting ordinarily has the effect of saving energy (a la cyclists in a
peloton), but if birds are gliding and already saving substantial energy by
not flapping their wings, I wondered whether any significant energy savings
benefit can be derived by aligning in vee formations while gliding. At
first I thought not, but gliding inevitably requires some energy - small
muscle coordination and positional adjustments - not as costly as flapping
wings, but some energy is required. When frigatebirds form vees, I
hypothesize there is in fact significant energy savings for those birds in
drafting positions - small muscle contractions for positional adjustments
may be reduced, and birds in these formations will expend less energy. They
would not, I suggest, align in these ways if it were not for some energy
savings benefit.

Because frigatebirds do not generate the higher air pressure behind which to
draft, such as geese do, or cyclists do, or fish in water do by propelling
themselves through the medium (air or water), I suggest this form of energy
savings constitutes a third type of "drafting". The other is energy
reduction by huddling, such as penguins undergo. So I suggest three types
of drafting occurrences:

I Occurs when system components generate effective air or
liquid pressure as they propel themselves through the medium; eg. cyclist
pelotons, fish schools, geese in vees;

II Occurs when system components remain stationery and air or
liquid pressure is generated externally; eg frigatebirds in vees while
gliding and remaining more or less positionally stable, and possibly some
types of fish (here I suggest this may occur in fish swimming upstream, such
as salmon, which may hold themselves in a stationery position against the
flow of the water - I haven't specifically observed any interesting drafting
formations as a result, although I have watched salmon swim upstream and
speculate drafting formations do occur)

III Occurs when system components remain stationery and
environment temperature drops; eg. penguin huddles

Type I exhibit phase changes from disordered states to ordered states and
back again through hysteresis loops. For cyclists, when peloton speeds are
higher than a critical speed/drafting threshold, disorder in the peloton
occurs. In a peloton, density is generally higher at low speeds and density
decreases as speeds increase. At a relatively high threshold speed, a
peloton loses cohesiveness entirely. To resume cohesion, peloton speeds
must fall to a lower threshold to resume cohesive formations (I've observed
and documented this). The loop is clockwise (speed on Y axis, density/order
on X) , but is the inverse of vehicle traffic hysteresis, for example, where
density increases as speed decreases (note that drafting is not a factor in
traffic).

For frigatebirds, because order increases as windspeed increases to a
threshold range, above which disorder occurs, wind speeds must only drop to
within the critical range for order to occur again. As a result the
hysteresis loop may not exist or is not as evident. I tentatively speculate
this windspeed range is approximately equivalent to the magnitude of
drafting benefit derived when birds are in drafting formations; similarly
the height of the hysteresis loop in drafting cyclists is related to the
drafting benefit derived (but may not precisely match it).

So drafting parameter seems to represent a constant that manifests itself in
related but different ways. For example, in Type 1 situations, drafting
parameter indicates the magnitude of the hysteresis loop; in Type II where
there is no hysteresis, drafting parameter indicates the magnitude of the
critical range of speeds within which certain formations occur. Drafting
parameter is thus also a general principle underlying the self-organized
complex behaviour of a number of different systems.

For Type III (penguin huddles), density/order increases as temperature drops
(requiring greater energy output to remain warm, so a decrease in
temperature is equivalent to an increase in speed in Type I situations);
density/order decreases as temperature increases to some threshold, after
which there is no huddle cohesion. Presumably at some very cold temperature
the huddle cannot generate enough heat and disintegrates by penguins
freezing to death. In the direction of temperature increase, the hysteresis
loop occurs when disorder occurs at a critical temperature, but must fall to
some lower threshold temperature for the huddle to occur again.

In any event there is a lot more analysis to be made, and I have more to say
even now, but here are a few observations. Basically, my point is that
through my frigatebird observations, I've identified a third type of
drafting situation. I had already identified the peloton (which is obvious
and well documented) and huddle situations (which is not as obvious and not
well documented). _____________

The second, slightly less rigourous observation I made when in Cancun was a
clustering effect among cabs. In Cancun, and likely many parts of Mexico,
all cabs are required to be of the same colors, so they are all easy to
spot. There are also many, many cabs in Cancun - it appears about one in
six vehicles is a taxi.

On the roads, it appeared to me that frequently cab clusters, or several
cabs near each other, would be driving within two degrees of each other,
often within one degree. One explanation is that they often originate in
the same location, many waiting at high person-density locations like the
airport, the bus station, etc. However, I am not sure this explains the
clustering on the roads, as cabs leaving from high density locations would
not leave simultaneously when fares are widely distributed in time; they
also do not have the same destinations. So, clustering must be due to
something else, I think.

Firstly, cab drivers tend to drive faster than the rest of the traffic,
especially when they have a fare on board. I am wondering if their fast
driving and deft abilities at weaving in and out of traffic allows them to
agglomerate at stop lights. As traffic approaches stop lights, the slower
driving traffic still leaves enough space for faster traffic further away
from the light to slip through and make up a few spaces, even as traffic
closest to the stop lights slow down and increase density. After a few such
lights, faster traffic "sifts" through to the front, and ends up at the
front. This is just an idea, and no doubt there are a number of problems
with it (for example if cabs also tend to go through yellow and red lights,
reducing agglomeration). Nonetheless, if the phenomenon is real - and I
observed it to occur more often than just chance would seem to explain -
then there must be a reason for it.

In any event, I would be interested in any input others may have about both
of these subjects.

Frank Wimberly

observations of complex phenomena while in Mexico

In addition to whatever aerodynamic advantage derives from the "V"
formation, another advantage might be that each bird (except the leader)
has only to keep one other bird in sight to maintain its position and,
therefore, to stay on course. The only other formation that I can think
of that has this property is a diagonal line--that is half a "V".

Maybe the frigate birds in Mazatlan had a destination (Cancun?) but the
ones in the Yucatan did not because it wasn't the season to migrate.
You were in Mazatlan in the fall. What time of the year were you in
Cancun?

Frank
---
Frank C. Wimberly
140 Calle Ojo Feliz (505) 995-8715 or (505) 670-9918 (cell)
Santa Fe, NM 87505 wimberly3 at earthlink.net

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On
Behalf Of Hugh Trenchard
Sent: Friday, January 05, 2007 7:42 PM
To: The Friday Morning Applied Complexity Coffee Group
Cc: Gottfried Mayer
Subject: [FRIAM] observations of complex phenomena while in Mexico

I am a lurker on this listserv and find many of the discussions here
interesting and valuable. Recently I was in Mexico and noticed a couple
of
interesting complex phenomena I thought I would share with this group.

The first relates to frigatebird formations and ties in with
observations of
these birds I made last year. Last year, when in Mazatlan, I noticed
that
frigatebirds often hover and glide for several minutes at a time without

flapping and that they tend to glide in disorderd configurations until
they
spontaneously undergo a phase change (it seems to me) when they align in
vee
formations - still gliding nonetheless. These are fantastic sights to
see,
since the birds seem to hang in the air in these vee formations without
passing across the sky at the relatively high speeds of geese, for
example.

This year, in Cancun, I noticed frigatebirds gliding in disordered
configurations and, waiting patiently for the phase change, I was
disappointed when these changes did not occur. I wondered if I was
imagining the alignments I saw last year in Mazatlan, but fairly certain
I
wasn't, I speculate why the phase changes did not occur among the birds
I
saw in Cancun. Firstly it's possible the frigatebird colonies on the
Caribbean side of Mexico simply don't undergo these formations, being a
slightly different sub-species or what have you. Perhaps, but I
hypothesize
that the wind speeds are the primary factor in determining whether
formation
phase changes occur.

In Mazatlan last year in late Sept/early October, the wind speeds were
low,
I recall. In Cancun, wind speeds were significantly higher. I suggest
that
gliding in vee formations can only occur between a certain range of wind

speed - if wind speed is too low, the birds cannot glide at all; if too
high, they can glide, but they cannot align in vee formations. The
critical
range allows frigate birds to draft when gliding behind another while
maintaining position, but above the range the drafting effect is too
high
and the birds get "sucked" through - or tend to fall, it looked to me -
the
low pressure areas and cannot hold their positions.

Drafting ordinarily has the effect of saving energy (a la cyclists in a
peloton), but if birds are gliding and already saving substantial energy
by
not flapping their wings, I wondered whether any significant energy
savings
benefit can be derived by aligning in vee formations while gliding. At
first I thought not, but gliding inevitably requires some energy - small

muscle coordination and positional adjustments - not as costly as
flapping
wings, but some energy is required. When frigatebirds form vees, I
hypothesize there is in fact significant energy savings for those birds
in
drafting positions - small muscle contractions for positional
adjustments
may be reduced, and birds in these formations will expend less energy.
They
would not, I suggest, align in these ways if it were not for some energy

savings benefit.

Because frigatebirds do not generate the higher air pressure behind
which to
draft, such as geese do, or cyclists do, or fish in water do by
propelling
themselves through the medium (air or water), I suggest this form of
energy
savings constitutes a third type of "drafting". The other is energy
reduction by huddling, such as penguins undergo. So I suggest three
types
of drafting occurrences:

I Occurs when system components generate effective air or
liquid pressure as they propel themselves through the medium; eg.
cyclist
pelotons, fish schools, geese in vees;

II Occurs when system components remain stationery and air
or
liquid pressure is generated externally; eg frigatebirds in vees while
gliding and remaining more or less positionally stable, and possibly
some
types of fish (here I suggest this may occur in fish swimming upstream,
such
as salmon, which may hold themselves in a stationery position against
the
flow of the water - I haven't specifically observed any interesting
drafting
formations as a result, although I have watched salmon swim upstream and

speculate drafting formations do occur)

III Occurs when system components remain stationery and
environment temperature drops; eg. penguin huddles

Type I exhibit phase changes from disordered states to ordered states
and
back again through hysteresis loops. For cyclists, when peloton speeds
are
higher than a critical speed/drafting threshold, disorder in the peloton

occurs. In a peloton, density is generally higher at low speeds and
density
decreases as speeds increase. At a relatively high threshold speed, a
peloton loses cohesiveness entirely. To resume cohesion, peloton speeds

must fall to a lower threshold to resume cohesive formations (I've
observed
and documented this). The loop is clockwise (speed on Y axis,
density/order
on X) , but is the inverse of vehicle traffic hysteresis, for example,
where
density increases as speed decreases (note that drafting is not a factor
in
traffic).

For frigatebirds, because order increases as windspeed increases to a
threshold range, above which disorder occurs, wind speeds must only drop
to
within the critical range for order to occur again. As a result the
hysteresis loop may not exist or is not as evident. I tentatively
speculate
this windspeed range is approximately equivalent to the magnitude of
drafting benefit derived when birds are in drafting formations;
similarly
the height of the hysteresis loop in drafting cyclists is related to the

drafting benefit derived (but may not precisely match it).

So drafting parameter seems to represent a constant that manifests
itself in
related but different ways. For example, in Type 1 situations, drafting

parameter indicates the magnitude of the hysteresis loop; in Type II
where
there is no hysteresis, drafting parameter indicates the magnitude of
the
critical range of speeds within which certain formations occur. Drafting

parameter is thus also a general principle underlying the self-organized

complex behaviour of a number of different systems.

For Type III (penguin huddles), density/order increases as temperature
drops
(requiring greater energy output to remain warm, so a decrease in
temperature is equivalent to an increase in speed in Type I situations);

density/order decreases as temperature increases to some threshold,
after
which there is no huddle cohesion. Presumably at some very cold
temperature
the huddle cannot generate enough heat and disintegrates by penguins
freezing to death. In the direction of temperature increase, the
hysteresis
loop occurs when disorder occurs at a critical temperature, but must
fall to
some lower threshold temperature for the huddle to occur again.

In any event there is a lot more analysis to be made, and I have more to
say
even now, but here are a few observations. Basically, my point is that
through my frigatebird observations, I've identified a third type of
drafting situation. I had already identified the peloton (which is
obvious
and well documented) and huddle situations (which is not as obvious and
not
well documented). _____________

The second, slightly less rigourous observation I made when in Cancun
was a
clustering effect among cabs. In Cancun, and likely many parts of
Mexico,
all cabs are required to be of the same colors, so they are all easy to
spot. There are also many, many cabs in Cancun - it appears about one
in
six vehicles is a taxi.

On the roads, it appeared to me that frequently cab clusters, or several

cabs near each other, would be driving within two degrees of each other,

often within one degree. One explanation is that they often originate
in
the same location, many waiting at high person-density locations like
the
airport, the bus station, etc. However, I am not sure this explains the

clustering on the roads, as cabs leaving from high density locations
would
not leave simultaneously when fares are widely distributed in time; they

also do not have the same destinations. So, clustering must be due to
something else, I think.

Firstly, cab drivers tend to drive faster than the rest of the traffic,
especially when they have a fare on board. I am wondering if their fast

driving and deft abilities at weaving in and out of traffic allows them
to
agglomerate at stop lights. As traffic approaches stop lights, the
slower
driving traffic still leaves enough space for faster traffic further
away
from the light to slip through and make up a few spaces, even as traffic

closest to the stop lights slow down and increase density. After a few
such
lights, faster traffic "sifts" through to the front, and ends up at the
front. This is just an idea, and no doubt there are a number of
problems
with it (for example if cabs also tend to go through yellow and red
lights,
reducing agglomeration). Nonetheless, if the phenomenon is real - and I

observed it to occur more often than just chance would seem to explain -

then there must be a reason for it.

In any event, I would be interested in any input others may have about
both
of these subjects.

============================================================
FRIAM Applied Complexity Group listserv
Meets Fridays 9a-11:30 at cafe at St. John's College
lectures, archives, unsubscribe, maps at http://www.friam.org

Phil Henshaw-2

observations of complex phenomena while in Mexico

In reply to this post by Hugh Trenchard

I just love watching birds and can see you do too! One behavior I like
especially is the flocking of birds at dusk. I don't know the details
of where they're headed or even why they'd eventually roost by the
hundreds in a single tree, but the way they soar in great weaving clouds
that are pulled apart as small groups leave and draw out others, to then
reform again and continue the dance, is just amazing. I've watched the
behavior with many species, city, country, different places. It always
comes clear to me that what they're doing is some kind of negotiation.
You have to ask, what's the sense of their being in such a big group in
the first place, and then why go through such extended gyrations, maybe
30-40 circles before deciding who sits where on what tree...

For another one, what do you think is going on with the apparent global
end of the great Canadian Geese migration? When I was a kid it was like
clockwork, twice a year we'd see these beautiful high altitude
formations of mysteriously honking great birds heading a couple thousand
miles north or south. Now it seems they just quit! and hang out in the
same parks and golf courses year round. That seems a very odd way to
end an ancient habit of having two homes, shifting, for me, from being
this remote beauty to an annoying local pest in just 30 years. That's
not evolution.

I think the idea that these fascinating patterns have some simple
explanation other than the behavior of the birds themselves is
questionable. We stumble into thinking that things are caused by the
effect they have, which is backwards of course. That reasoning was
popularized by, and somewhat reasonable for, genetic evolution where
you're dealing with a record keeping system that's fairly reliable and
can record some kinds of effects for the future instances of a behavior.
For how birds socialize I think something else is needed. To me many
things like these are better explained by looking at the opportunities
being taken rather than the necessities being imposed, but that's a
longer story.

Anyway, my guess on why the Mazatlan frigatebirds went into set V
formations after a period of gliding and the ones in Cancun didn't is
that they were different birds, with different social habits. It could
be that the ones you saw in Mazatlan were a community with strong
leaders and the ones in Cancun weren't, or something. Clearly it's a
whole lot easier to marvel at them than really understand what's
happening.

Phil Henshaw ????.?? ? `?.????
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
680 Ft. Washington Ave
NY NY 10040
tel: 212-795-4844
e-mail: pfh at synapse9.com
explorations: www.synapse9.com

> -----Original Message-----
> From: friam-bounces at redfish.com
> [mailto:friam-bounces at redfish.com] On Behalf Of Hugh Trenchard
> Sent: Friday, January 05, 2007 9:42 PM
> To: The Friday Morning Applied Complexity Coffee Group
> Cc: Gottfried Mayer
> Subject: [FRIAM] observations of complex phenomena while in Mexico
>
>
> I am a lurker on this listserv and find many of the discussions here
> interesting and valuable. Recently I was in Mexico and
> noticed a couple of
> interesting complex phenomena I thought I would share with this group.
>
> The first relates to frigatebird formations and ties in with
> observations of
> these birds I made last year. Last year, when in Mazatlan, I
> noticed that
> frigatebirds often hover and glide for several minutes at a
> time without
> flapping and that they tend to glide in disorderd
> configurations until they
> spontaneously undergo a phase change (it seems to me) when
> they align in vee
> formations - still gliding nonetheless. These are fantastic
> sights to see,
> since the birds seem to hang in the air in these vee
> formations without
> passing across the sky at the relatively high speeds of
> geese, for example.
>
> This year, in Cancun, I noticed frigatebirds gliding in disordered
> configurations and, waiting patiently for the phase change, I was
> disappointed when these changes did not occur. I wondered if I was
> imagining the alignments I saw last year in Mazatlan, but
> fairly certain I
> wasn't, I speculate why the phase changes did not occur among
> the birds I
> saw in Cancun. Firstly it's possible the frigatebird colonies on the
> Caribbean side of Mexico simply don't undergo these
> formations, being a
> slightly different sub-species or what have you. Perhaps,
> but I hypothesize
> that the wind speeds are the primary factor in determining
> whether formation
> phase changes occur.
>
> In Mazatlan last year in late Sept/early October, the wind
> speeds were low,
> I recall. In Cancun, wind speeds were significantly higher.
> I suggest that
> gliding in vee formations can only occur between a certain
> range of wind
> speed - if wind speed is too low, the birds cannot glide at
> all; if too
> high, they can glide, but they cannot align in vee
> formations. The critical
> range allows frigate birds to draft when gliding behind another while
> maintaining position, but above the range the drafting effect
> is too high
> and the birds get "sucked" through - or tend to fall, it
> looked to me - the
> low pressure areas and cannot hold their positions.
>
> Drafting ordinarily has the effect of saving energy (a la
> cyclists in a
> peloton), but if birds are gliding and already saving
> substantial energy by
> not flapping their wings, I wondered whether any significant
> energy savings
> benefit can be derived by aligning in vee formations while
> gliding. At
> first I thought not, but gliding inevitably requires some
> energy - small
> muscle coordination and positional adjustments - not as
> costly as flapping
> wings, but some energy is required. When frigatebirds form vees, I
> hypothesize there is in fact significant energy savings for
> those birds in
> drafting positions - small muscle contractions for positional
> adjustments
> may be reduced, and birds in these formations will expend
> less energy. They
> would not, I suggest, align in these ways if it were not for
> some energy
> savings benefit.
>
> Because frigatebirds do not generate the higher air pressure
> behind which to
> draft, such as geese do, or cyclists do, or fish in water do
> by propelling
> themselves through the medium (air or water), I suggest this
> form of energy
> savings constitutes a third type of "drafting". The other is energy
> reduction by huddling, such as penguins undergo. So I
> suggest three types
> of drafting occurrences:
>
> I Occurs when system components generate
> effective air or
> liquid pressure as they propel themselves through the medium;
> eg. cyclist
> pelotons, fish schools, geese in vees;
>
> II Occurs when system components remain
> stationery and air or
> liquid pressure is generated externally; eg frigatebirds in
> vees while
> gliding and remaining more or less positionally stable, and
> possibly some
> types of fish (here I suggest this may occur in fish swimming
> upstream, such
> as salmon, which may hold themselves in a stationery position
> against the
> flow of the water - I haven't specifically observed any
> interesting drafting
> formations as a result, although I have watched salmon swim
> upstream and
> speculate drafting formations do occur)
>
> III Occurs when system components remain stationery and
> environment temperature drops; eg. penguin huddles
>
> Type I exhibit phase changes from disordered states to
> ordered states and
> back again through hysteresis loops. For cyclists, when
> peloton speeds are
> higher than a critical speed/drafting threshold, disorder in
> the peloton
> occurs. In a peloton, density is generally higher at low
> speeds and density
> decreases as speeds increase. At a relatively high threshold
> speed, a
> peloton loses cohesiveness entirely. To resume cohesion,
> peloton speeds
> must fall to a lower threshold to resume cohesive formations
> (I've observed
> and documented this). The loop is clockwise (speed on Y
> axis, density/order
> on X) , but is the inverse of vehicle traffic hysteresis, for
> example, where
> density increases as speed decreases (note that drafting is
> not a factor in
> traffic).
>
> For frigatebirds, because order increases as windspeed increases to a
> threshold range, above which disorder occurs, wind speeds
> must only drop to
> within the critical range for order to occur again. As a result the
> hysteresis loop may not exist or is not as evident. I
> tentatively speculate
> this windspeed range is approximately equivalent to the magnitude of
> drafting benefit derived when birds are in drafting
> formations; similarly
> the height of the hysteresis loop in drafting cyclists is
> related to the
> drafting benefit derived (but may not precisely match it).
>
> So drafting parameter seems to represent a constant that
> manifests itself in
> related but different ways. For example, in Type 1
> situations, drafting
> parameter indicates the magnitude of the hysteresis loop; in
> Type II where
> there is no hysteresis, drafting parameter indicates the
> magnitude of the
> critical range of speeds within which certain formations
> occur. Drafting
> parameter is thus also a general principle underlying the
> self-organized
> complex behaviour of a number of different systems.
>
> For Type III (penguin huddles), density/order increases as
> temperature drops
> (requiring greater energy output to remain warm, so a decrease in
> temperature is equivalent to an increase in speed in Type I
> situations);
> density/order decreases as temperature increases to some
> threshold, after
> which there is no huddle cohesion. Presumably at some very
> cold temperature
> the huddle cannot generate enough heat and disintegrates by penguins
> freezing to death. In the direction of temperature increase,
> the hysteresis
> loop occurs when disorder occurs at a critical temperature,
> but must fall to
> some lower threshold temperature for the huddle to occur again.
>
> In any event there is a lot more analysis to be made, and I
> have more to say
> even now, but here are a few observations. Basically, my
> point is that
> through my frigatebird observations, I've identified a third type of
> drafting situation. I had already identified the peloton
> (which is obvious
> and well documented) and huddle situations (which is not as
> obvious and not
> well documented). _____________
>
> The second, slightly less rigourous observation I made when
> in Cancun was a
> clustering effect among cabs. In Cancun, and likely many
> parts of Mexico,
> all cabs are required to be of the same colors, so they are
> all easy to
> spot. There are also many, many cabs in Cancun - it appears
> about one in
> six vehicles is a taxi.
>
> On the roads, it appeared to me that frequently cab clusters,
> or several
> cabs near each other, would be driving within two degrees of
> each other,
> often within one degree. One explanation is that they often
> originate in
> the same location, many waiting at high person-density
> locations like the
> airport, the bus station, etc. However, I am not sure this
> explains the
> clustering on the roads, as cabs leaving from high density
> locations would
> not leave simultaneously when fares are widely distributed in
> time; they
> also do not have the same destinations. So, clustering must
> be due to
> something else, I think.
>
> Firstly, cab drivers tend to drive faster than the rest of
> the traffic,
> especially when they have a fare on board. I am wondering if
> their fast
> driving and deft abilities at weaving in and out of traffic
> allows them to
> agglomerate at stop lights. As traffic approaches stop
> lights, the slower
> driving traffic still leaves enough space for faster traffic
> further away
> from the light to slip through and make up a few spaces, even
> as traffic
> closest to the stop lights slow down and increase density.
> After a few such
> lights, faster traffic "sifts" through to the front, and ends
> up at the
> front. This is just an idea, and no doubt there are a number
> of problems
> with it (for example if cabs also tend to go through yellow
> and red lights,
> reducing agglomeration). Nonetheless, if the phenomenon is
> real - and I
> observed it to occur more often than just chance would seem
> to explain -
> then there must be a reason for it.
>
> In any event, I would be interested in any input others may
> have about both
> of these subjects.
>
>
>
>
>
>
> ============================================================
> FRIAM Applied Complexity Group listserv
> Meets Fridays 9a-11:30 at cafe at St. John's College
> lectures, archives, unsubscribe, maps at http://www.friam.org
>
>

Carl Tollander

observations of complex phenomena while in Mexico

In reply to this post by Hugh Trenchard

Curious. I was wondering if, since the frigatebirds are aligning into
formations without
flapping, if it would be easier to perceive if there were differences in
the "yaw" of the
bird wing or body relative to its position in the formation. If so,
several hypotheses
about aerodynamics on formation might be arise. If, for example, there
was a pronounced
yaw to the right on the right side of the V due purely to the drafting
aerodynamics of the
V (this is just an example) then the bird in its local frame might be
adjusting its position
relative to the bird in front, which would be somewhat to the left of
where it "should" be,
(given the local aerodynamic properties of the surrounding air
(temperature, pressure, wind speed, etc)
so the bird would work harder to adjust its position so that the bird in
front would be
more in the expected position. At some point the energy advantage gained
by remaining
in the V formation would be lost, and the V would not be supportable.

Frigatebirds are relatively large, so the idea here is that any drafting
effect would not occur
uniformly on any given bird in a V formation, possibly causing various
local yaws and compensations.

Carl

Hugh Trenchard wrote:

> I am a lurker on this listserv and find many of the discussions here
> interesting and valuable. Recently I was in Mexico and noticed a couple of
> interesting complex phenomena I thought I would share with this group.
>
> The first relates to frigatebird formations and ties in with observations of
> these birds I made last year. Last year, when in Mazatlan, I noticed that
> frigatebirds often hover and glide for several minutes at a time without
> flapping and that they tend to glide in disorderd configurations until they
> spontaneously undergo a phase change (it seems to me) when they align in vee
> formations - still gliding nonetheless. These are fantastic sights to see,
> since the birds seem to hang in the air in these vee formations without
> passing across the sky at the relatively high speeds of geese, for example.
>
> This year, in Cancun, I noticed frigatebirds gliding in disordered
> configurations and, waiting patiently for the phase change, I was
> disappointed when these changes did not occur. I wondered if I was
> imagining the alignments I saw last year in Mazatlan, but fairly certain I
> wasn't, I speculate why the phase changes did not occur among the birds I
> saw in Cancun. Firstly it's possible the frigatebird colonies on the
> Caribbean side of Mexico simply don't undergo these formations, being a
> slightly different sub-species or what have you. Perhaps, but I hypothesize
> that the wind speeds are the primary factor in determining whether formation
> phase changes occur.
>
> In Mazatlan last year in late Sept/early October, the wind speeds were low,
> I recall. In Cancun, wind speeds were significantly higher. I suggest that
> gliding in vee formations can only occur between a certain range of wind
> speed - if wind speed is too low, the birds cannot glide at all; if too
> high, they can glide, but they cannot align in vee formations. The critical
> range allows frigate birds to draft when gliding behind another while
> maintaining position, but above the range the drafting effect is too high
> and the birds get "sucked" through - or tend to fall, it looked to me - the
> low pressure areas and cannot hold their positions.
>
> Drafting ordinarily has the effect of saving energy (a la cyclists in a
> peloton), but if birds are gliding and already saving substantial energy by
> not flapping their wings, I wondered whether any significant energy savings
> benefit can be derived by aligning in vee formations while gliding. At
> first I thought not, but gliding inevitably requires some energy - small
> muscle coordination and positional adjustments - not as costly as flapping
> wings, but some energy is required. When frigatebirds form vees, I
> hypothesize there is in fact significant energy savings for those birds in
> drafting positions - small muscle contractions for positional adjustments
> may be reduced, and birds in these formations will expend less energy. They
> would not, I suggest, align in these ways if it were not for some energy
> savings benefit.
>
> Because frigatebirds do not generate the higher air pressure behind which to
> draft, such as geese do, or cyclists do, or fish in water do by propelling
> themselves through the medium (air or water), I suggest this form of energy
> savings constitutes a third type of "drafting". The other is energy
> reduction by huddling, such as penguins undergo. So I suggest three types
> of drafting occurrences:
>
> I Occurs when system components generate effective air or
> liquid pressure as they propel themselves through the medium; eg. cyclist
> pelotons, fish schools, geese in vees;
>
> II Occurs when system components remain stationery and air or
> liquid pressure is generated externally; eg frigatebirds in vees while
> gliding and remaining more or less positionally stable, and possibly some
> types of fish (here I suggest this may occur in fish swimming upstream, such
> as salmon, which may hold themselves in a stationery position against the
> flow of the water - I haven't specifically observed any interesting drafting
> formations as a result, although I have watched salmon swim upstream and
> speculate drafting formations do occur)
>
> III Occurs when system components remain stationery and
> environment temperature drops; eg. penguin huddles
>
> Type I exhibit phase changes from disordered states to ordered states and
> back again through hysteresis loops. For cyclists, when peloton speeds are
> higher than a critical speed/drafting threshold, disorder in the peloton
> occurs. In a peloton, density is generally higher at low speeds and density
> decreases as speeds increase. At a relatively high threshold speed, a
> peloton loses cohesiveness entirely. To resume cohesion, peloton speeds
> must fall to a lower threshold to resume cohesive formations (I've observed
> and documented this). The loop is clockwise (speed on Y axis, density/order
> on X) , but is the inverse of vehicle traffic hysteresis, for example, where
> density increases as speed decreases (note that drafting is not a factor in
> traffic).
>
> For frigatebirds, because order increases as windspeed increases to a
> threshold range, above which disorder occurs, wind speeds must only drop to
> within the critical range for order to occur again. As a result the
> hysteresis loop may not exist or is not as evident. I tentatively speculate
> this windspeed range is approximately equivalent to the magnitude of
> drafting benefit derived when birds are in drafting formations; similarly
> the height of the hysteresis loop in drafting cyclists is related to the
> drafting benefit derived (but may not precisely match it).
>
> So drafting parameter seems to represent a constant that manifests itself in
> related but different ways. For example, in Type 1 situations, drafting
> parameter indicates the magnitude of the hysteresis loop; in Type II where
> there is no hysteresis, drafting parameter indicates the magnitude of the
> critical range of speeds within which certain formations occur. Drafting
> parameter is thus also a general principle underlying the self-organized
> complex behaviour of a number of different systems.
>
> For Type III (penguin huddles), density/order increases as temperature drops
> (requiring greater energy output to remain warm, so a decrease in
> temperature is equivalent to an increase in speed in Type I situations);
> density/order decreases as temperature increases to some threshold, after
> which there is no huddle cohesion. Presumably at some very cold temperature
> the huddle cannot generate enough heat and disintegrates by penguins
> freezing to death. In the direction of temperature increase, the hysteresis
> loop occurs when disorder occurs at a critical temperature, but must fall to
> some lower threshold temperature for the huddle to occur again.
>
> In any event there is a lot more analysis to be made, and I have more to say
> even now, but here are a few observations. Basically, my point is that
> through my frigatebird observations, I've identified a third type of
> drafting situation. I had already identified the peloton (which is obvious
> and well documented) and huddle situations (which is not as obvious and not
> well documented). _____________
>
> The second, slightly less rigourous observation I made when in Cancun was a
> clustering effect among cabs. In Cancun, and likely many parts of Mexico,
> all cabs are required to be of the same colors, so they are all easy to
> spot. There are also many, many cabs in Cancun - it appears about one in
> six vehicles is a taxi.
>
> On the roads, it appeared to me that frequently cab clusters, or several
> cabs near each other, would be driving within two degrees of each other,
> often within one degree. One explanation is that they often originate in
> the same location, many waiting at high person-density locations like the
> airport, the bus station, etc. However, I am not sure this explains the
> clustering on the roads, as cabs leaving from high density locations would
> not leave simultaneously when fares are widely distributed in time; they
> also do not have the same destinations. So, clustering must be due to
> something else, I think.
>
> Firstly, cab drivers tend to drive faster than the rest of the traffic,
> especially when they have a fare on board. I am wondering if their fast
> driving and deft abilities at weaving in and out of traffic allows them to
> agglomerate at stop lights. As traffic approaches stop lights, the slower
> driving traffic still leaves enough space for faster traffic further away
> from the light to slip through and make up a few spaces, even as traffic
> closest to the stop lights slow down and increase density. After a few such
> lights, faster traffic "sifts" through to the front, and ends up at the
> front. This is just an idea, and no doubt there are a number of problems
> with it (for example if cabs also tend to go through yellow and red lights,
> reducing agglomeration). Nonetheless, if the phenomenon is real - and I
> observed it to occur more often than just chance would seem to explain -
> then there must be a reason for it.
>
> In any event, I would be interested in any input others may have about both
> of these subjects.
>
>
>
>
>
>
> ============================================================
> FRIAM Applied Complexity Group listserv
> Meets Fridays 9a-11:30 at cafe at St. John's College
> lectures, archives, unsubscribe, maps at http://www.friam.org
>
>
>
>

Hugh Trenchard

observations of complex phenomena while in Mexico

Thanks for all your comments. Next time I'm in Mexico, I will definitely do
my best to get some video footage. My recollection of what I saw in October
2005 in Mazatlan is that the various yaws and compensations were easy to
see, as you say. I can't remember how long the formations were stable -
perhaps generally less than a minute, before the formation would break down
(but I'm really just guessing) - but they were long enough to see the
dynamics involved. And after the formations broke down, they would often
reform again fairly soon.

Regarding Phil's comment that the Mazatlan colonies were possibly just
different from the Cancun colonies I will need to investigate that.
(Frank - I was in Cancun over Christmas, by the way and the migration habits
might be a factor involved in when and why they engage in vee formation -
something else to investigate). It seems, though, it is unlikely that a
single colony in Mazatlan would have developed the vee formation capacity
completely independently of a colony in Cancun, especially when the distance
between them is not really that great when we think in terms of bird
migratory habits. So far, I still think the wind conditions are more likely
what prevented vee formation in Cancun, but of course I will need a bit more
evidence to support that.

Also, Phil, I would argue that strong leadership is not a factor in vee
formations. As we all know, self-organized phenomena arise without leaders
to guide the emergent patterns - I can't think of why it would be any
different for frigatebirds. The formations must self-organize from some
principle of interaction - in the case of organisms that save energy by
drafting, it is the coupling between them that occurs because there is a
physiological or energetic advantage to their coupling (ie. to their
drafting).

It could be that frigatebird vee formations are simply derived from their
inherent natural behaviours and have no basis in any underlying physical
principles, but given the advantages conferred upon other types of organisms
that engage in drafting dynamics and formations, it seems reasonable to ask
if there is there is a physical principle underlying the formations.

Nonetheless, what this all suggests to me that it is an area ripe for
further study, and that very little work has been done to establish the
universality of the "drafting principle" as I am calling it. I actually
think it applies in a lot of other situations as well, from trail formation
to aspects of economics, but that's little more than a gut feeling at this
point. But I suppose, at the very least, until I can get some good footage
of frigatebird formations and some wind speed measurements, we can only
speculate as to what is happening with them.

I'm not sure when I'll be in Mexico next, but I'll keep everyone posted as
to what I see. If anyone else is going, please keep an eye out for the
frigatebirds! Pelicans also fly in vees too, but they are more like geese,
I think - they fly past at fairly high speed.

On the note about the decline of traveling geese, I really can't speculate.
I live on the west coast of Canada in British Columbia and I still see vee
formations going in all directions. But perhaps global warming is a factor
in the distances they need to fly now - maybe they can stay farther north
all year round.

Hugh Trenchard

----- Original Message -----
From: "Carl Tollander" <[hidden email]>
To: "The Friday Morning Applied Complexity Coffee Group" <friam at redfish.com>
Sent: Friday, January 05, 2007 10:16 PM
Subject: Re: [FRIAM] observations of complex phenomena while in Mexico

> Curious. I was wondering if, since the frigatebirds are aligning into
> formations without
> flapping, if it would be easier to perceive if there were differences in
> the "yaw" of the
> bird wing or body relative to its position in the formation. If so,
> several hypotheses
> about aerodynamics on formation might be arise. If, for example, there
> was a pronounced
> yaw to the right on the right side of the V due purely to the drafting
> aerodynamics of the
> V (this is just an example) then the bird in its local frame might be
> adjusting its position
> relative to the bird in front, which would be somewhat to the left of
> where it "should" be,
> (given the local aerodynamic properties of the surrounding air
> (temperature, pressure, wind speed, etc)
> so the bird would work harder to adjust its position so that the bird in
> front would be
> more in the expected position. At some point the energy advantage gained
> by remaining
> in the V formation would be lost, and the V would not be supportable.
>
> Frigatebirds are relatively large, so the idea here is that any drafting
> effect would not occur
> uniformly on any given bird in a V formation, possibly causing various
> local yaws and compensations.
>
> Carl
>
> Hugh Trenchard wrote:
>> I am a lurker on this listserv and find many of the discussions here
>> interesting and valuable. Recently I was in Mexico and noticed a couple
>> of
>> interesting complex phenomena I thought I would share with this group.
>>
>> The first relates to frigatebird formations and ties in with observations
>> of
>> these birds I made last year. Last year, when in Mazatlan, I noticed
>> that
>> frigatebirds often hover and glide for several minutes at a time without
>> flapping and that they tend to glide in disorderd configurations until
>> they
>> spontaneously undergo a phase change (it seems to me) when they align in
>> vee
>> formations - still gliding nonetheless. These are fantastic sights to
>> see,
>> since the birds seem to hang in the air in these vee formations without
>> passing across the sky at the relatively high speeds of geese, for
>> example.
>>
>> This year, in Cancun, I noticed frigatebirds gliding in disordered
>> configurations and, waiting patiently for the phase change, I was
>> disappointed when these changes did not occur. I wondered if I was
>> imagining the alignments I saw last year in Mazatlan, but fairly certain
>> I
>> wasn't, I speculate why the phase changes did not occur among the birds I
>> saw in Cancun. Firstly it's possible the frigatebird colonies on the
>> Caribbean side of Mexico simply don't undergo these formations, being a
>> slightly different sub-species or what have you. Perhaps, but I
>> hypothesize
>> that the wind speeds are the primary factor in determining whether
>> formation
>> phase changes occur.
>>
>> In Mazatlan last year in late Sept/early October, the wind speeds were
>> low,
>> I recall. In Cancun, wind speeds were significantly higher. I suggest
>> that
>> gliding in vee formations can only occur between a certain range of wind
>> speed - if wind speed is too low, the birds cannot glide at all; if too
>> high, they can glide, but they cannot align in vee formations. The
>> critical
>> range allows frigate birds to draft when gliding behind another while
>> maintaining position, but above the range the drafting effect is too high
>> and the birds get "sucked" through - or tend to fall, it looked to me -
>> the
>> low pressure areas and cannot hold their positions.
>>
>> Drafting ordinarily has the effect of saving energy (a la cyclists in a
>> peloton), but if birds are gliding and already saving substantial energy
>> by
>> not flapping their wings, I wondered whether any significant energy
>> savings
>> benefit can be derived by aligning in vee formations while gliding. At
>> first I thought not, but gliding inevitably requires some energy - small
>> muscle coordination and positional adjustments - not as costly as
>> flapping
>> wings, but some energy is required. When frigatebirds form vees, I
>> hypothesize there is in fact significant energy savings for those birds
>> in
>> drafting positions - small muscle contractions for positional adjustments
>> may be reduced, and birds in these formations will expend less energy.
>> They
>> would not, I suggest, align in these ways if it were not for some energy
>> savings benefit.
>>
>> Because frigatebirds do not generate the higher air pressure behind which
>> to
>> draft, such as geese do, or cyclists do, or fish in water do by
>> propelling
>> themselves through the medium (air or water), I suggest this form of
>> energy
>> savings constitutes a third type of "drafting". The other is energy
>> reduction by huddling, such as penguins undergo. So I suggest three
>> types
>> of drafting occurrences:
>>
>> I Occurs when system components generate effective air or
>> liquid pressure as they propel themselves through the medium; eg. cyclist
>> pelotons, fish schools, geese in vees;
>>
>> II Occurs when system components remain stationery and air
>> or
>> liquid pressure is generated externally; eg frigatebirds in vees while
>> gliding and remaining more or less positionally stable, and possibly some
>> types of fish (here I suggest this may occur in fish swimming upstream,
>> such
>> as salmon, which may hold themselves in a stationery position against the
>> flow of the water - I haven't specifically observed any interesting
>> drafting
>> formations as a result, although I have watched salmon swim upstream and
>> speculate drafting formations do occur)
>>
>> III Occurs when system components remain stationery and
>> environment temperature drops; eg. penguin huddles
>>
>> Type I exhibit phase changes from disordered states to ordered states and
>> back again through hysteresis loops. For cyclists, when peloton speeds
>> are
>> higher than a critical speed/drafting threshold, disorder in the peloton
>> occurs. In a peloton, density is generally higher at low speeds and
>> density
>> decreases as speeds increase. At a relatively high threshold speed, a
>> peloton loses cohesiveness entirely. To resume cohesion, peloton speeds
>> must fall to a lower threshold to resume cohesive formations (I've
>> observed
>> and documented this). The loop is clockwise (speed on Y axis,
>> density/order
>> on X) , but is the inverse of vehicle traffic hysteresis, for example,
>> where
>> density increases as speed decreases (note that drafting is not a factor
>> in
>> traffic).
>>
>> For frigatebirds, because order increases as windspeed increases to a
>> threshold range, above which disorder occurs, wind speeds must only drop
>> to
>> within the critical range for order to occur again. As a result the
>> hysteresis loop may not exist or is not as evident. I tentatively
>> speculate
>> this windspeed range is approximately equivalent to the magnitude of
>> drafting benefit derived when birds are in drafting formations; similarly
>> the height of the hysteresis loop in drafting cyclists is related to the
>> drafting benefit derived (but may not precisely match it).
>>
>> So drafting parameter seems to represent a constant that manifests itself
>> in
>> related but different ways. For example, in Type 1 situations, drafting
>> parameter indicates the magnitude of the hysteresis loop; in Type II
>> where
>> there is no hysteresis, drafting parameter indicates the magnitude of the
>> critical range of speeds within which certain formations occur. Drafting
>> parameter is thus also a general principle underlying the self-organized
>> complex behaviour of a number of different systems.
>>
>> For Type III (penguin huddles), density/order increases as temperature
>> drops
>> (requiring greater energy output to remain warm, so a decrease in
>> temperature is equivalent to an increase in speed in Type I situations);
>> density/order decreases as temperature increases to some threshold, after
>> which there is no huddle cohesion. Presumably at some very cold
>> temperature
>> the huddle cannot generate enough heat and disintegrates by penguins
>> freezing to death. In the direction of temperature increase, the
>> hysteresis
>> loop occurs when disorder occurs at a critical temperature, but must fall
>> to
>> some lower threshold temperature for the huddle to occur again.
>>
>> In any event there is a lot more analysis to be made, and I have more to
>> say
>> even now, but here are a few observations. Basically, my point is that
>> through my frigatebird observations, I've identified a third type of
>> drafting situation. I had already identified the peloton (which is
>> obvious
>> and well documented) and huddle situations (which is not as obvious and
>> not
>> well documented). _____________
>>
>> The second, slightly less rigourous observation I made when in Cancun was
>> a
>> clustering effect among cabs. In Cancun, and likely many parts of Mexico,
>> all cabs are required to be of the same colors, so they are all easy to
>> spot. There are also many, many cabs in Cancun - it appears about one in
>> six vehicles is a taxi.
>>
>> On the roads, it appeared to me that frequently cab clusters, or several
>> cabs near each other, would be driving within two degrees of each other,
>> often within one degree. One explanation is that they often originate in
>> the same location, many waiting at high person-density locations like the
>> airport, the bus station, etc. However, I am not sure this explains the
>> clustering on the roads, as cabs leaving from high density locations
>> would
>> not leave simultaneously when fares are widely distributed in time; they
>> also do not have the same destinations. So, clustering must be due to
>> something else, I think.
>>
>> Firstly, cab drivers tend to drive faster than the rest of the traffic,
>> especially when they have a fare on board. I am wondering if their fast
>> driving and deft abilities at weaving in and out of traffic allows them
>> to
>> agglomerate at stop lights. As traffic approaches stop lights, the
>> slower
>> driving traffic still leaves enough space for faster traffic further away
>> from the light to slip through and make up a few spaces, even as traffic
>> closest to the stop lights slow down and increase density. After a few
>> such
>> lights, faster traffic "sifts" through to the front, and ends up at the
>> front. This is just an idea, and no doubt there are a number of problems
>> with it (for example if cabs also tend to go through yellow and red
>> lights,
>> reducing agglomeration). Nonetheless, if the phenomenon is real - and I
>> observed it to occur more often than just chance would seem to explain -
>> then there must be a reason for it.
>>
>> In any event, I would be interested in any input others may have about
>> both
>> of these subjects.
>>
>>
>>
>>
>>
>>
>> ============================================================
>> FRIAM Applied Complexity Group listserv
>> Meets Fridays 9a-11:30 at cafe at St. John's College
>> lectures, archives, unsubscribe, maps at http://www.friam.org
>>
>>
>>
>>
>
> ============================================================
> FRIAM Applied Complexity Group listserv
> Meets Fridays 9a-11:30 at cafe at St. John's College
> lectures, archives, unsubscribe, maps at http://www.friam.org

Phil Henshaw-2

observations of complex phenomena while in Mexico

I'll be glad to see what further patterns you find. Just to clarify, my
suggestion was not just that the two colonies were different, but that
the variation in local colony behavior might be as great as the
variation in local environments where colonies are found. If you were
to make observations randomly across the range of the species you'd get
a better sense of what behaviors are universal and what are local. What
you'd want is a work-around, of course, that would be a little less
work. Perhaps you could try getting a list of bird watchers in the
frigatebird range and randomly calling them to see what they have to
say.

As to the generality of a "drafting principle", there is at least one
major example of it I've given a good bit of study, the formation and
evolution of air currents. If you want an example of the vast
creativity of local physical processes you might do well to give them a
little look. Do all the modeling you like and none of it will produce
the degree of intricate and inventive complexity you find in the pathway
negotiations taking place around any even mildly warm body like, for
example, the one sitting in front of your computer screen right now!

Phil Henshaw ????.?? ? `?.????
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
680 Ft. Washington Ave
NY NY 10040
tel: 212-795-4844
e-mail: pfh at synapse9.com
explorations: www.synapse9.com

> -----Original Message-----
> From: friam-bounces at redfish.com
> [mailto:friam-bounces at redfish.com] On Behalf Of Hugh Trenchard
> Sent: Saturday, January 06, 2007 7:16 PM
> To: The Friday Morning Applied Complexity Coffee Group
> Subject: Re: [FRIAM] observations of complex phenomena while in Mexico
>
>
> Thanks for all your comments. Next time I'm in Mexico, I will
> definitely do
> my best to get some video footage. My recollection of what I
> saw in October
> 2005 in Mazatlan is that the various yaws and compensations
> were easy to
> see, as you say. I can't remember how long the formations
> were stable -
> perhaps generally less than a minute, before the formation
> would break down
> (but I'm really just guessing) - but they were long enough to see the
> dynamics involved. And after the formations broke down, they
> would often
> reform again fairly soon.
>
> Regarding Phil's comment that the Mazatlan colonies were
> possibly just
> different from the Cancun colonies I will need to investigate that.
> (Frank - I was in Cancun over Christmas, by the way and the
> migration habits
> might be a factor involved in when and why they engage in vee
> formation -
> something else to investigate). It seems, though, it is
> unlikely that a
> single colony in Mazatlan would have developed the vee
> formation capacity
> completely independently of a colony in Cancun, especially
> when the distance
> between them is not really that great when we think in terms of bird
> migratory habits. So far, I still think the wind conditions
> are more likely
> what prevented vee formation in Cancun, but of course I will
> need a bit more
> evidence to support that.
>
> Also, Phil, I would argue that strong leadership is not a
> factor in vee
> formations. As we all know, self-organized phenomena arise
> without leaders
> to guide the emergent patterns - I can't think of why it would be any
> different for frigatebirds. The formations must self-organize
> from some
> principle of interaction - in the case of organisms that save
> energy by
> drafting, it is the coupling between them that occurs because
> there is a
> physiological or energetic advantage to their coupling (ie. to their
> drafting).
>
> It could be that frigatebird vee formations are simply
> derived from their
> inherent natural behaviours and have no basis in any
> underlying physical
> principles, but given the advantages conferred upon other
> types of organisms
> that engage in drafting dynamics and formations, it seems
> reasonable to ask
> if there is there is a physical principle underlying the formations.
>
> Nonetheless, what this all suggests to me that it is an area ripe for
> further study, and that very little work has been done to
> establish the
> universality of the "drafting principle" as I am calling it.
> I actually
> think it applies in a lot of other situations as well, from
> trail formation
> to aspects of economics, but that's little more than a gut
> feeling at this
> point. But I suppose, at the very least, until I can get
> some good footage
> of frigatebird formations and some wind speed measurements,
> we can only
> speculate as to what is happening with them.
>
> I'm not sure when I'll be in Mexico next, but I'll keep
> everyone posted as
> to what I see. If anyone else is going, please keep an eye
> out for the
> frigatebirds! Pelicans also fly in vees too, but they are
> more like geese,
> I think - they fly past at fairly high speed.
>
> On the note about the decline of traveling geese, I really
> can't speculate.
> I live on the west coast of Canada in British Columbia and I
> still see vee
> formations going in all directions. But perhaps global
> warming is a factor
> in the distances they need to fly now - maybe they can stay
> farther north
> all year round.
>
> Hugh Trenchard
>
>

Hugh Trenchard

frigatebirds - short video

http://ibc.hbw.com/ibc/phtml/votacio.phtml?idVideo=3621&tipus=1

Here is a link to a short video which provides a small inkling of the
"drafting" behaviour or frigatebirds. It isn't a long enough video to know
if the alignment there was more than accidental, nor does it show more than
two in alignment, but it's a start. Thanks for the suggestion about
contacting bird-watchers in frigatebird territory for a work-around, I'll
look into it.

Hugh

----- Original Message -----
From: "Phil Henshaw" <[hidden email]>
To: "'The Friday Morning Applied Complexity Coffee Group'"
<friam at redfish.com>
Sent: Saturday, January 06, 2007 9:28 PM
Subject: Re: [FRIAM] observations of complex phenomena while in Mexico

I'll be glad to see what further patterns you find. Just to clarify, my
suggestion was not just that the two colonies were different, but that
the variation in local colony behavior might be as great as the
variation in local environments where colonies are found. If you were
to make observations randomly across the range of the species you'd get
a better sense of what behaviors are universal and what are local. What
you'd want is a work-around, of course, that would be a little less
work. Perhaps you could try getting a list of bird watchers in the
frigatebird range and randomly calling them to see what they have to
say.

As to the generality of a "drafting principle", there is at least one
major example of it I've given a good bit of study, the formation and
evolution of air currents. If you want an example of the vast
creativity of local physical processes you might do well to give them a
little look. Do all the modeling you like and none of it will produce
the degree of intricate and inventive complexity you find in the pathway
negotiations taking place around any even mildly warm body like, for
example, the one sitting in front of your computer screen right now!

Phil Henshaw ????.?? ? `?.????
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
680 Ft. Washington Ave
NY NY 10040
tel: 212-795-4844
e-mail: pfh at synapse9.com
explorations: www.synapse9.com

============================================================
FRIAM Applied Complexity Group listserv
Meets Fridays 9a-11:30 at cafe at St. John's College
lectures, archives, unsubscribe, maps at http://www.friam.org

Parks, Raymond

observations of complex phenomena while in Mexico

In reply to this post by Hugh Trenchard

Hugh Trenchard wrote:
> Thanks for all your comments.

I just now had a moment to try and catch up with FRIAM and read your
thread.

As far as drafting goes, I would suggest that there may be some use
of wingtip vortices, a normally harmful phenomenon.

> Also, Phil, I would argue that strong leadership is not a factor in vee
> formations. As we all know, self-organized phenomena arise without leaders
> to guide the emergent patterns - I can't think of why it would be any
> different for frigatebirds. The formations must self-organize from some
> principle of interaction - in the case of organisms that save energy by
> drafting, it is the coupling between them that occurs because there is a
> physiological or energetic advantage to their coupling (ie. to their
> drafting).

At least with respect to geese, the leadership of the formation
changes frequently.

> On the note about the decline of traveling geese, I really can't speculate.
> I live on the west coast of Canada in British Columbia and I still see vee
> formations going in all directions. But perhaps global warming is a factor
> in the distances they need to fly now - maybe they can stay farther north
> all year round.

I think the primary driver of the decline of traveling geese is
burgeoning population. There now are so many geese that the full
population may not be supportable in the northern latitudes, even during
summer. I know that I live on what is a major migration path with the
winter home of geese about a hundred miles south of ABQ. Right now, we
have tens of thousands of geese who have made a permanent home in the
central Rio Grande valley, where I live. One interesting aspect of this
is that the coyotes in the village of Corrales, my home town, are
starting to exhibit cardiac problems from eating too much rich food.

--
Ray Parks rcparks at sandia.gov
IDART Project Lead Voice:505-844-4024
IORTA Department Mobile:505-238-9359
http://www.sandia.gov/scada Fax:505-844-9641
http://www.sandia.gov/idart Pager:800-690-5288

Phil Henshaw-2

frigatebirds - short video

In reply to this post by Hugh Trenchard

That video is very nice for putting it into context. There's an
appearance, for that 10 seconds, that one pair are flying together in
locked position and another is in the group mixing positions. Is that
what you first meant by the first two parts of "often hover and glide
for several minutes at a time without flapping and that they tend to
glide in disordered configurations until they spontaneously undergo a
phase change"?

I was also hoping I could get you to clarify a comment you made about my
suggestion that some communities might have more 'leadership' (i.e.
social structure). You said "As we all know, self-organized phenomena
arise without leaders to guide the emergent patterns - I can't think of
why it would be any different for frigatebirds." I would be surprised
if you thought self-organization in sand piles and communities of
intelligent species happened the same way. Peter described how the
birds would be able to physically feel the 'V' formation effect, and I
was essentially suggesting that some communities may have stronger group
awareness into which that would fit.

For much of the instrumental mechanisms of natural system behaviors like
these we're left wildly guessing, of course. I just try to balance the
shakiness of my foundations for it with my confidence in the
conclusions, always looking for the strong foundation of the behavior's
particular growth dynamic as an anchor.

Phil Henshaw ????.?? ? `?.????
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
680 Ft. Washington Ave
NY NY 10040
tel: 212-795-4844
e-mail: pfh at synapse9.com
explorations: www.synapse9.com

> -----Original Message-----
> From: friam-bounces at redfish.com
> [mailto:friam-bounces at redfish.com] On Behalf Of Hugh Trenchard
> Sent: Sunday, January 07, 2007 1:15 PM
> To: The Friday Morning Applied Complexity Coffee Group
> Subject: Re: [FRIAM] frigatebirds - short video
>
>
> http://ibc.hbw.com/ibc/phtml/votacio.phtml?idVideo=3621&tipus=1
>
> Here is a link to a short video which provides a small inkling of the
> "drafting" behaviour or frigatebirds. It isn't a long enough
> video to know
> if the alignment there was more than accidental, nor does it
> show more than
> two in alignment, but it's a start. Thanks for the suggestion about
> contacting bird-watchers in frigatebird territory for a
> work-around, I'll
> look into it.
>
> Hugh
>
>
> ----- Original Message -----
> From: "Phil Henshaw" <sy at synapse9.com>
> To: "'The Friday Morning Applied Complexity Coffee Group'"
> <friam at redfish.com>
> Sent: Saturday, January 06, 2007 9:28 PM
> Subject: Re: [FRIAM] observations of complex phenomena while in Mexico
>
>
> I'll be glad to see what further patterns you find. Just to
> clarify, my suggestion was not just that the two colonies
> were different, but that the variation in local colony
> behavior might be as great as the
> variation in local environments where colonies are found.
> If you were
> to make observations randomly across the range of the species
> you'd get a better sense of what behaviors are universal and
> what are local. What you'd want is a work-around, of course,
> that would be a little less work. Perhaps you could try
> getting a list of bird watchers in the frigatebird range and
> randomly calling them to see what they have to say.
>
> As to the generality of a "drafting principle", there is at
> least one major example of it I've given a good bit of
> study, the formation and evolution of air currents. If you
> want an example of the vast creativity of local physical
> processes you might do well to give them a
> little look. Do all the modeling you like and none of it
> will produce
> the degree of intricate and inventive complexity you find in
> the pathway negotiations taking place around any even mildly
> warm body like, for example, the one sitting in front of your
> computer screen right now!
>
>
> Phil Henshaw ????.?? ? `?.????
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 680 Ft. Washington Ave
> NY NY 10040
> tel: 212-795-4844
> e-mail: pfh at synapse9.com
> explorations: www.synapse9.com
>
>
> > -----Original Message-----
> > From: friam-bounces at redfish.com
> [mailto:friam-bounces at redfish.com] On
> > Behalf Of Hugh Trenchard
> > Sent: Saturday, January 06, 2007 7:16 PM
> > To: The Friday Morning Applied Complexity Coffee Group
> > Subject: Re: [FRIAM] observations of complex phenomena
> while in Mexico
> >
> >
> > Thanks for all your comments. Next time I'm in Mexico, I will
> > definitely do my best to get some video footage. My
> recollection of
> > what I saw in October
> > 2005 in Mazatlan is that the various yaws and compensations
> > were easy to
> > see, as you say. I can't remember how long the formations
> > were stable -
> > perhaps generally less than a minute, before the formation
> > would break down
> > (but I'm really just guessing) - but they were long enough
> to see the
> > dynamics involved. And after the formations broke down, they
> > would often
> > reform again fairly soon.
> >
> > Regarding Phil's comment that the Mazatlan colonies were
> possibly just
> > different from the Cancun colonies I will need to investigate that.
> > (Frank - I was in Cancun over Christmas, by the way and the
> > migration habits
> > might be a factor involved in when and why they engage in vee
> > formation -
> > something else to investigate). It seems, though, it is
> > unlikely that a
> > single colony in Mazatlan would have developed the vee
> > formation capacity
> > completely independently of a colony in Cancun, especially
> > when the distance
> > between them is not really that great when we think in terms of bird
> > migratory habits. So far, I still think the wind conditions
> > are more likely
> > what prevented vee formation in Cancun, but of course I will
> > need a bit more
> > evidence to support that.
> >
> > Also, Phil, I would argue that strong leadership is not a factor in
> > vee formations. As we all know, self-organized phenomena arise
> > without leaders
> > to guide the emergent patterns - I can't think of why it
> would be any
> > different for frigatebirds. The formations must self-organize
> > from some
> > principle of interaction - in the case of organisms that save
> > energy by
> > drafting, it is the coupling between them that occurs because
> > there is a
> > physiological or energetic advantage to their coupling (ie. to their
> > drafting).
> >
> > It could be that frigatebird vee formations are simply derived from
> > their inherent natural behaviours and have no basis in any
> > underlying physical
> > principles, but given the advantages conferred upon other
> > types of organisms
> > that engage in drafting dynamics and formations, it seems
> > reasonable to ask
> > if there is there is a physical principle underlying the formations.
> >
> > Nonetheless, what this all suggests to me that it is an
> area ripe for
> > further study, and that very little work has been done to establish
> > the universality of the "drafting principle" as I am calling it.
> > I actually
> > think it applies in a lot of other situations as well, from
> > trail formation
> > to aspects of economics, but that's little more than a gut
> > feeling at this
> > point. But I suppose, at the very least, until I can get
> > some good footage
> > of frigatebird formations and some wind speed measurements,
> > we can only
> > speculate as to what is happening with them.
> >
> > I'm not sure when I'll be in Mexico next, but I'll keep everyone
> > posted as to what I see. If anyone else is going, please
> keep an eye
> > out for the
> > frigatebirds! Pelicans also fly in vees too, but they are
> > more like geese,
> > I think - they fly past at fairly high speed.
> >
> > On the note about the decline of traveling geese, I really can't
> > speculate. I live on the west coast of Canada in British
> Columbia and
> > I still see vee
> > formations going in all directions. But perhaps global
> > warming is a factor
> > in the distances they need to fly now - maybe they can stay
> > farther north
> > all year round.
> >
> > Hugh Trenchard
> >
> >
>
>
>
> ============================================================
> FRIAM Applied Complexity Group listserv
> Meets Fridays 9a-11:30 at cafe at St. John's College
> lectures, archives, unsubscribe, maps at http://www.friam.org
>
>
>
>
> ============================================================
> FRIAM Applied Complexity Group listserv
> Meets Fridays 9a-11:30 at cafe at St. John's College
> lectures, archives, unsubscribe, maps at http://www.friam.org
>
>

Hugh Trenchard

frigatebirds - short video

Phil,

Thanks for the follow up. As Dr. Lissaman says in a subsequent post, that
clip by itself may say nothing, but it's only an indication of the type of
formations I was referring to, namely a complete vee formation without
flapping that I observed (while gliding, and in relatively stationery
positions - ie. not moving across the sky at high speed), but not shown in
that short video. The "phase change" I referred to would have involved
several frigate birds in the formation like the two shown next to each other
in the video.

By the way, I would say that there may be forms of coupling that go on when
two lions on the savannah walk side-by-side. For example their gaits may be
synchronized or phase-locked. It would be interesting to see what emergent
patterns might arise if you put one hundred globally coupled in that
fashion, side-by-side and set them all walking.

My thought on the leadership question is that the frigatebirds wouldn't
undergo a "phase change" unless there was some energy reduction benefit for
them to do so. This would be an evolutionary development and in my mind
would apply across species. But as you or someone pointed out, there are
ways to confirm that, as I certainly can't state that as a fact. There may
be elements of leadership involved, but in my mind any emergent formations
are more likely to result from local physical rules, although I can imagine
some emergent patterns could arise from a combination of leadership and
local physical rules, and there probably are plenty of examples of that.

In terms of "physically feeling the vee formation effect", I would argue
that they can certainly feel the reduction in energy output required in the
most efficient positions, and perhaps are aware of the positions of other
birds in their field of view and perhaps have seen other Vees off in the
distance, but they end up in their formations because they learned,
originally by accident at some stage in their evolutionary development, that
there was smaller energy output in certain positions. My point is they
could very well not be aware of the global pattern they are forming, just as
in a much larger flock, birds will only be aware of their immediate
neighbours.

>From my experience as a bicycle racer, it's obvious that cyclists can feel
the physiological benefits of certain formations, but in a large peloton,
the cyclists may easily not be aware of certain pattern formations, which
become observable only from the air and upon a closer analysis of their
global movements.

I agree that we are largely guessing when determining the underlying
mechanisms for certain behaviours, but if we can find similar behaviours
among different groups, and can identify mechanisms underlying one group,
then it is some evidence similar mechanisms apply to the other groups. Not
proof obviously, but it is *some* evidence, and it is certainly cause for
closer investigation for the curious minded.

----- Original Message -----
From: "Phil Henshaw" <[hidden email]>
To: "'The Friday Morning Applied Complexity Coffee Group'"
<friam at redfish.com>
Sent: Tuesday, January 09, 2007 4:55 AM
Subject: Re: [FRIAM] frigatebirds - short video

That video is very nice for putting it into context. There's an
appearance, for that 10 seconds, that one pair are flying together in
locked position and another is in the group mixing positions. Is that
what you first meant by the first two parts of "often hover and glide
for several minutes at a time without flapping and that they tend to
glide in disordered configurations until they spontaneously undergo a
phase change"?

I was also hoping I could get you to clarify a comment you made about my
suggestion that some communities might have more 'leadership' (i.e.
social structure). You said "As we all know, self-organized phenomena
arise without leaders to guide the emergent patterns - I can't think of
why it would be any different for frigatebirds." I would be surprised
if you thought self-organization in sand piles and communities of
intelligent species happened the same way. Peter described how the
birds would be able to physically feel the 'V' formation effect, and I
was essentially suggesting that some communities may have stronger group
awareness into which that would fit.

For much of the instrumental mechanisms of natural system behaviors like
these we're left wildly guessing, of course. I just try to balance the
shakiness of my foundations for it with my confidence in the
conclusions, always looking for the strong foundation of the behavior's
particular growth dynamic as an anchor.

Phil Henshaw ????.?? ? `?.????
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
680 Ft. Washington Ave
NY NY 10040
tel: 212-795-4844
e-mail: pfh at synapse9.com
explorations: www.synapse9.com

Phil Henshaw-2

frigatebirds - short video

Oh yes! It's an important reservation that "they could very well not be
aware of the global pattern they are forming, just as in a much larger
flock, birds will [may] only be aware of their immediate neighbours."
In evo. bio. the phrase is that "A is random with respect to B". It is
quite common for things produced by one mechanism are instrumental to
another mechanism which develops quite independently. Most natural
systems develop from 'found objects', as it were.

Now it's possible in a case like this that the social behavior which
makes a bird discover the energy saving groove of 'V' formation flight
is partly evolved and recorded in their DNA. Relying on that, though,
is like throwing darts at a black hole in my way of thinking, your dart
just disappears because it only identifies an assumption. I don't see
how in this case, but sometimes you can identify a larger property, like
if you saw birds 'dropping in' on a forming 'V' rather than 'shaking
out' into the 'V' form. Watching the details of how things happen is
often very helpful.

Phil Henshaw ????.?? ? `?.????
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
680 Ft. Washington Ave
NY NY 10040
tel: 212-795-4844
e-mail: pfh at synapse9.com
explorations: www.synapse9.com

> -----Original Message-----
> From: friam-bounces at redfish.com
> [mailto:friam-bounces at redfish.com] On Behalf Of Hugh Trenchard
> Sent: Wednesday, January 10, 2007 2:04 AM
> To: The Friday Morning Applied Complexity Coffee Group
> Subject: Re: [FRIAM] frigatebirds - short video
>
>
>
> Phil,
>
> Thanks for the follow up. As Dr. Lissaman says in a
> subsequent post, that
> clip by itself may say nothing, but it's only an indication
> of the type of
> formations I was referring to, namely a complete vee
> formation without
> flapping that I observed (while gliding, and in relatively stationery
> positions - ie. not moving across the sky at high speed), but
> not shown in
> that short video. The "phase change" I referred to would
> have involved
> several frigate birds in the formation like the two shown
> next to each other
> in the video.
>
> By the way, I would say that there may be forms of coupling
> that go on when
> two lions on the savannah walk side-by-side. For example
> their gaits may be
> synchronized or phase-locked. It would be interesting to see
> what emergent
> patterns might arise if you put one hundred globally coupled in that
> fashion, side-by-side and set them all walking.
>
> My thought on the leadership question is that the
> frigatebirds wouldn't
> undergo a "phase change" unless there was some energy
> reduction benefit for
> them to do so. This would be an evolutionary development and
> in my mind
> would apply across species. But as you or someone pointed
> out, there are
> ways to confirm that, as I certainly can't state that as a
> fact. There may
> be elements of leadership involved, but in my mind any
> emergent formations
> are more likely to result from local physical rules, although
> I can imagine
> some emergent patterns could arise from a combination of
> leadership and
> local physical rules, and there probably are plenty of
> examples of that.
>
> In terms of "physically feeling the vee formation effect", I
> would argue
> that they can certainly feel the reduction in energy output
> required in the
> most efficient positions, and perhaps are aware of the
> positions of other
> birds in their field of view and perhaps have seen other Vees
> off in the
> distance, but they end up in their formations because they learned,
> originally by accident at some stage in their evolutionary
> development, that
> there was smaller energy output in certain positions. My
> point is they
> could very well not be aware of the global pattern they are
> forming, just as
> in a much larger flock, birds will only be aware of their immediate
> neighbours.
>
> >From my experience as a bicycle racer, it's obvious that
> cyclists can
> >feel
> the physiological benefits of certain formations, but in a
> large peloton,
> the cyclists may easily not be aware of certain pattern
> formations, which
> become observable only from the air and upon a closer
> analysis of their
> global movements.
>
> I agree that we are largely guessing when determining the underlying
> mechanisms for certain behaviours, but if we can find similar
> behaviours
> among different groups, and can identify mechanisms
> underlying one group,
> then it is some evidence similar mechanisms apply to the
> other groups. Not
> proof obviously, but it is *some* evidence, and it is
> certainly cause for
> closer investigation for the curious minded.
>
>

Hugh Trenchard

frigatebirds - short video

Thanks. The only complex group dynamic I can claim any special knowledge of
is a bicycle peloton, and if I apply the "dropping in" effect and the
"shaking out" effect, I recognize that a bicycle peloton is both a
socialized phenomena and a purely self-organized one. It is also a good
example of a dynamic that is both leader-driven and self-organized.

An example of "dropping in" occurs when a lone rider sees a peloton of
riders ahead, speeds up to catch the group because he knows for a fact that
he will save energy by riding with the group. That's a socialized response,
because he has learned or been taught that there is energy savings in a
group through drafting.

Once he is part of the group, the main physical parameters are energy
savings by drafting and collision avoidance. Both of these result in
continuous positional adjustments within the peloton. A combined
physical/social pattern to result is positional rotation within the
peloton - physical because riders at the front sometimes become so fatigued
that fresh riders behind simply ride past the fatiguing riders, who can then
drop into drafting positions to recover; socialized because riders are also
taught to trade positions.

If we think of the source of the emergent patterns as a ratio of physical to
social behaviour, then as riders at the front of the peloton approach their
phsysiological thresholds, the ratio of physical/social increases. That is,
their fatigue is likely to force a reduction in output so they can recover,
while fresher riders behind maintain speed and pass the fatiguing riders.
In other words, any speed or power output increases that intitially led to
these physiological thresholds may have been leader induced, but once
cyclists approach thresholds, then the pure limits of physiology and physics
take over.

There are many nuances to this analysis of pelotons, but before I get too
profuse here, my main point is that your suggestion of a "dropping in" and
"shaking out analysis" is very helpful, and I agree there is a lot to be
learned from it.

By the way - in addition to this discussion, were there any comments on my
second main observation in Mexico - the "cab sifting" effect in traffic?

Hugh Trenchard

----- Original Message -----
From: "Phil Henshaw" <[hidden email]>
To: "'The Friday Morning Applied Complexity Coffee Group'"
<friam at redfish.com>
Sent: Wednesday, January 10, 2007 3:50 AM
Subject: Re: [FRIAM] frigatebirds - short video

Oh yes! It's an important reservation that "they could very well not be
aware of the global pattern they are forming, just as in a much larger
flock, birds will [may] only be aware of their immediate neighbours."
In evo. bio. the phrase is that "A is random with respect to B". It is
quite common for things produced by one mechanism are instrumental to
another mechanism which develops quite independently. Most natural
systems develop from 'found objects', as it were.

Now it's possible in a case like this that the social behavior which
makes a bird discover the energy saving groove of 'V' formation flight
is partly evolved and recorded in their DNA. Relying on that, though,
is like throwing darts at a black hole in my way of thinking, your dart
just disappears because it only identifies an assumption. I don't see
how in this case, but sometimes you can identify a larger property, like
if you saw birds 'dropping in' on a forming 'V' rather than 'shaking
out' into the 'V' form. Watching the details of how things happen is
often very helpful.

Phil Henshaw ????.?? ? `?.????
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
680 Ft. Washington Ave
NY NY 10040
tel: 212-795-4844
e-mail: pfh at synapse9.com
explorations: www.synapse9.com